Actually when I eat out (hasn't happened in a while), your first picture is usually my type of "starter." XD That, or chips and salsa if we're talking about Mexican restaurants.

There's one woman I follow with a local restaurant blog and I think she takes half her food home on a regular basis and uses it for another meal. I couldn't eat out as much as she does.

But I think as a general rule of thumb, expect at least two meals worth of food at a sit-down restaurant in the US unless you know how their portion sizes run (you can always order something else if you are still hungry), and from your report, sounds like you could potentially add Canada to that list, too.